feat: add export button pulse animation when ready

[kunal-yelgate]

Description

Closes #236

Overview

Adds a subtle pulse animation to the Export button to guide user attention when a file has been loaded and export settings are ready.

Changes

• Added pulse animation to the Export button when:

  • file is set
  • status === 'idle'

• Removed the animation when:

  • Export is in progress
  • Export has completed
  • No file is loaded

• Added support for prefers-reduced-motion to disable the animation for users who have motion reduction enabled.

Testing

• Verified the pulse animation appears only when the editor is ready to export.
• Verified the animation stops during export and after export completion.
• Verified the animation is disabled when prefers-reduced-motion is enabled.
• Ran local development environment and confirmed expected behavior.

Acceptance Criteria

• ✅ Subtle pulse animation when ready to export
• ✅ Animation stops during and after export
• ✅ Respects prefers-reduced-motion

[vercel]

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A member of the Team first needs to authorize it.

[github-actions]

👋 Thanks for your PR, @kunal-yelgate!

Welcome to Reframe — a browser-based video editor built for everyone 🎬

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Quick checklist

• PR title follows Conventional Commits (e.g. feat: add dark mode)
• Linked the issue this PR closes (e.g. Closes #123)
• Tested the changes locally (bun run dev)
• Build passes (bun run build)

Useful links

• 📖 CONTRIBUTING.md
• 🐛 Open Issues
• ⭐ Star the repo to support the project!

Happy coding! 🎉

[github-actions]

✅ PR Format Check Passed — @kunal-yelgate

Basic format checks passed. A maintainer will review your code changes.

This does not mean the PR is approved — it just means the format is correct.

[kunal-yelgate]

Hey @magic-peach review the PR

[kunal-yelgate]

resolve the workflow issue